It really depends on the book and the writer. It's about clear communication. There are some arguments to be made for the reader not to have a clear delineation in this shift in perspective, depending on the nature of the story.

I say: do whatever works for the story. If no headings gets in the way of the story, use headings. If no headings adds to or helps the story in some way, don't use them. If it really doesn't matter to what you are trying to communicate, I'd default to using them as some readers may find them handy and the others will just glide past them.